The Federal Trade Commission filed a lawsuit Tuesday to block Amgen Inc. from purchasing Horizon Therapeutics for $27.8 billion, out of concerns the merger would harm patients on Horizon’s two fastest-growing drugs.
Amgen’s acquisition of Horizon was first announced in December as a way for the company to bolster its portfolio of drugs to treat rare diseases and acquire Horizon’s two most notable rare disease drugs, Tepezza and Krystexxa.
Tepezza, an FDA-approved treatment for moderate to severe thyroid eye disease, had almost $2 billion in sales last year, Krystexxa, a gout therapy, drew $716 million in sales—neither drug has any competition.
The FTC argued Amgen could pressure pharmacy benefit managers to favor Tepezza and Krystexxa by offering bundles with other drugs and generous rebates, making it harder for smaller companies to release competitors to the two drugs.
The lawsuit to stop the merger comes in response to complaints to the FTC about rebates and fees paid by drug manufacturers to pharmaceutical benefit managers and others in order to favor high-cost drugs, according to the agency.
Amgen, one of the world’s leading biotechnology companies, won a bidding war to buy Horizon last year against rivals Sanofi and Johnson & Johnson. The sale was the largest pharmaceutical transaction proposed in 2022. Amgen has over 20 products on the market—including big names Enbrel, Prolia and Otezla—but has a few drugs reaching the end of their patents. The merger with Horizon, and its rare disease drugs, was seen as a way to smooth out Amgen’s revenues while patents expire and the company waits for FDA approval of other drugs.
“Rampant consolidation in the pharmaceutical industry has given powerful companies a pass to exorbitantly hike prescription drug prices, deny patients access to more affordable generics, and hamstring innovation in life-saving markets,” said FTC Bureau of Competition Director Holly Vedova in a press release.